1. Technical Field
The present invention relates to copper alloy wires and methods for producing copper alloy wires.
2. Description of Related Art
Known copper alloys for wires include copper-zirconium alloys. For example, PTL 1 proposes a copper alloy wire with improved electrical conductivity and ultimate tensile strength produced by subjecting an alloy containing 0.01% to 0.50% by weight of zirconium to solution treatment, drawing the alloy to the final diameter, and subjecting the wire to predetermined aging treatment. This copper alloy wire has Cu3Zr precipitated in copper matrix phases to achieve a high strength up to 730 MPa. In PTL 2, on the other hand, the present inventors have proposed a copper alloy containing 0.05 to 8.0 atomic percent of zirconium and having a two-phase structure in which copper matrix phases and eutectic phases of copper and a copper-zirconium compound are layered on top of each other and in which the adjacent copper matrix phase crystal grains contact intermittently, thus achieving a high strength up to 1,250 MPa.